Office



(No Model.)

W. HQM'QGOY.

CHUCK.

No. 568,539. f Patented Sept. 29, 1896.

\A/ITIJ;EEE S 'NVENTDR w g g UNITED STATES ATENT' FFICEQ WILLIAM II. MCCOY, OF MILLERS FALLS, MASSACHUSETTS, ASSIGNOR TO THE MILLERS FALLS COMPANY, OF SAME PLACE.

CHUCK.

SPECIFICATION forming part of Letters Patent No. 568,539, dated September 29, 1896.

Application filed December 28, 1895. Serial No. 572,975. (No model. 1

To all whom it may concern.-

Be it known that I, WVILLIAM I-I. MCCOY, of Millers Falls, in the county of Franklin and State of Massachusetts, have invented a certain new and useful Improvement in Chucks, of which the following, taken in connection with the accompanying drawings, is a specification. I

My present invention relates to chucks for holding tools and other articles; and the particular improvements therein consist in simplifying the parts, whereby the cost of manufacture is cheapened, in obviating the necessity of using any form of spring, and in the strength, durability, and positiveness of its action.

In the drawings, Figure 1 represents the chuck complete and holding a drill. Fig. 2 represents the shell detached from the socket. Fig. 3 represents a sectional elevation. Fig. 4 represents a cross-section on linex ocof Fig. 3. Fig. 5 represents one of the jaws.

A is the shell, having a tapering end a to fit over the lower end of the tapering socket and jaws and being threaded internally at a to fit thread 0 on exterior of socket C. The socket C has, preferably, three slots 0 to receive the jaws d. On each side of the slots is provided a recess 0 These recesses, being formed upon the exterior of the tapering part of the socket C, of course are beveled, the bevel corresponding with the taper of the lower end of socket C, as shown in Figs. 2 and 3. The interior of socket C is also threaded, c, to correspond with the threaded end I) of spindle B.

The jaws cl are formed tapering, as shown in Figs. 3 and 5, and a pin 01, extending on each side of the jaw, is placed nearly midway in its length and quite near theouter side of the edge of the jaw as placed in the slot of the socket. The pin 61', which extends through the jaw, projecting on each side, may be divided into two parts and a short pin inserted one on each side, each having the necessary projection. The projecting ends of the pin, when the jaw is in place, rest upon the beveled recess 0 and support the jaw in proper position, and must be placed substantially as indicated to prevent the jaw from falling inwardly and also to keep the jaw in ward, and the lower end contracting with the lower ends of the jaws cl forces them outward. The jaws sliding on the bevel-recesses c and being held in place by the shell A are forced together and tightly grip the tool or article placed between them. Upon unscrewing the parts, that is, withdrawing the spindle and holding the lower end of the chuck upward, the jaws drop back by their own weight, automatically opening outwardly, yet being held inplace by the pins resting in the beveled or tapering recesses 0 until the pins rest on the stops or ends of the recesses.

The distance the jaws can move is' regulated by the length of the recesses 0 the ends 0 c forming stops. The quickness of operation depends chiefly upon the pitch of the bevel, or, in general terms, the quickness of the taper c of the socket C. I prefer to use three jaws, but do not confine myself to that number. By this construction it will be observed that I do away with the use of springs and avoid any devices that may easily break or get out of order.

I do not employ any special device for drawing back the jaws, as the beveled recesses afford an easy and unobstructed support and guide for the jaws, held in place by the pins, and the pins easily sliding upon the sides of the recesses. The outer side of the recess is, of course, covered by the interior of the shell A, as fully shown in Fig. '3.

The spindle B may be attached to a handle or brace, or the chuck may be used in other ways as desired.

I am aware that chucks have been made with movable jaws arranged to be guided by a contrivance fitted into a mortise formed in the socket and arranged to hold a disk the edge of which projected into a slot made in one side of the jaw, as shown in the patent of Butler, No. 356,616; also that various forms of springs have been used to hold the jaws in place or aid in their movements, but neither of these constructions constitute the spirit of my invention, as I do away with all springs and so arrange the operative parts that the jaws are equally supported on both sides and cannot bind or stick, are self-acting without the aid of springs, are cheap of construction, and are not liable to get out of order. These advantages I obtain by my con struction, particularly by the use of the fixed supporting-pin (Z and the solid smooth surfaces formed upon the exterior of the socket as described, upon which the pin slides and by which alone the jaws are supported, held, and guided. I believe these peculiarities of my invention are new and valuable.

Having now fully described my invention, what I claim, and desire to secure by Letters Patent of the United States, is-

1. In a chuck, the tapering socket 0, provided with the exterior recess 0 the jaws cl, provided with the pins 01, placed midway of the length of said jaws and near the outer side of the same, and a suitable spindle and shell, combined and adapted to operate, substantially as set forth.

2. The combination of the screw-threaded spindle B; the socket 0, formed tapering and slotted near its lower end, and provided with beveled recesses, arranged to regulate the distance the jaws can be operated in open ing and closing; the jaws (I, provided with pins (1, and the shell A, formed to correspond with the taper of the socket, all substantially as set forth.

3. In a chuck, a socket provided with slots and beveled recesses for receiving the jaws; jaws having supporting-pins, adapted to rest upon and move on and within said beveled recesses; a spindle adapted to force the jaws outwardly and a shell formed to inclose the socket and jaws, all combined for the purposes set forth.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, on this 19th day of December, A. D. 1895.

WILLIAM H. MCCOY.

\Vitnesses:

E. L. ELLIOT, GEO. W. Nuts. 

